Serum procalcitonin in uncomplicated falciparum malaria: a preliminary study.

Background: Procalcitonin (PCT) has been found elevated in complicated forms of Plasmodium falciparum malaria. Its usefulness has almost never been assessed in uncomplicated falciparum malaria.

Method: We assessed diagnostic and prognostic value of PCT in a prospective series of 25 adults with uncomplicated P. falciparum malaria. Patients originated mainly from western Africa and were infected during a stay back in their native country (19 semi-immune and 6 non-immune subjects; 11 had not received any chemoprophylaxis).

Results: Parasitaemia ranged from 0.01 to 3%. Eighteen patients had their first PCT determined at admission or within 24h thereafter (mean +/- SD: 3.0 +/- 4.6 ng/ml; range: 0.1-19.7). PCT was higher than 0.5 ng/ml in 14 patients (78%), higher than 2 ng/ml in 7 (39%). PCT correlated with parasitaemia (r = 0.53; p = 0.027), not with C-reactive protein (CRP). Delay between first symptoms and diagnosis was much longer among patients with PCT higher than 2 ng/ml than among those with a lower PCT.

Conclusion: PCT was often elevated in uncomplicated malaria, especially when delay between first symptoms and diagnosis was long or parasitaemia was high (prognostic marker).